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The success of liver transplantation has led to the demand for donor organs far outstripping supply. Nearly one in 10 waitlisted patients die before an organ becomes available (http://www.unos.org). Allocating donor organs in a fair manner has been a challenge. The current allocation system for livers, theoretically built upon the principle of “sickest first” and the subject of great efforts to create the system in an equitable fashion, is recognized by medical professionals and patients alike as being imperfect. Patients with identical types and degrees of liver disease can wait disparate amounts of time according to an array of factors that are variably outside of their control. Factors that can influence access to donor organs include local organ donation rates, donation service area size/population, number of regional transplant centers, blood type, age (e.g. child vs. adult), indication for transplantation (hepatocellular carcinoma [HCC] vs. other indications), wealth and celebrity. In this issue of the journal, Schuetz et al [1] provide a detailed and elegant analysis of the impact of two variables on organ access: Model for End-stage Liver Disease (MELD) exception points granted systematically for HCC and geographic variation in organ availability. The primary basis for performing the analysis was the notion that the number of exception MELD points granted for HCC overestimates mortality risk. The main findings of the study are that HCC candidates are transplanted at higher rates than non-HCC candidates and are less likely to die on the waitlist. Remarkably, the overall risk of death decreases by 1% per MELD point for HCC, but increases by 7% for non-HCC patients (p < 0.0001). Similarly, the risk of posttransplant mortality also trended downward by 2% per MELD point for HCC patients, but increases by 3% per MELD point in non-HCC patients (p < 0.005). The authors reasonably conclude that increasing wait time impacts HCC candidates less than non-HCC candidates and note that under increased competition for donor organs, HCC candidates' advantage increases. Or, put simply, patients with HCC are unnecessarily favored in the current deceased donor organ allocation system. Organ allocation is a zero sum affair—an organ allocated to one patient denies access to and benefit from that organ for everyone else on the waitlist. The inevitable result of the disproportionate adjustment of MELD score for patients with HCC is that non-HCC patients, who must compete with HCC patients for donor organs, have unnecessarily diminished access to and spend more time waiting for liver transplantation. As time waiting for liver transplantation is strongly associated with mortality risk, the net effect of the current United Network for Organ Sharing (UNOS) HCC MELD exception points policy is excessive and avoidable waitlist mortality for non-HCC patients. The timing of the study by Schuetz et al [1] is ironic. The recently enacted and well-intended “Share 35” policy will increase access to donor organs for patients with HCC, as under this policy, HCC patients with MELD scores ≥35 now enjoy access to donor organs throughout the UNOS region in which they are listed. As one-fifth of deceased donor organs are allocated to patients with HCC, the issue is pressing. How did we arrive at this unhappy juncture and why has a patently unfair system not been fixed?

Allocating donor organs is a complex enterprise, regulated by the National Organ Transplant Act, passed by Congress in 1984, calling for a national unified transplant network (referred to as the Organ Procurement and Transplantation Network [OPTN]). The OPTN is responsible for overseeing the procurement, allocation and transplantation of solid organs across the country. The UNOS was awarded the initial OPTN contract in 1986, and has continued to administer the OPTN ever since. Since its inception, the national organ allocation system has been plagued by iniquities of access to donor organs. Between 1986 and 1997, patients waiting for transplantation in their respective Organ Procurement Organization/Donation Service Area were prioritized based on their hospital status and time on the waitinglist. The initial system was marginally improved in 1998 by implementation of a new system incorporating the Child–Turcotte–Pugh score, a relatively subjective index of severity of liver disease, and estimated life expectancy. The subjective elements and inherently weak predictivity of the components of this revised system ultimately proved unworkable. The US Department of Health and Human Services intervened in 1998 and challenged the transplant community with its first “Final Rule,” which sought to “assure that allocation of scarce organs [would] be based on common medical criteria, not accidents of geography.” There was sufficient opposition to the “Final Rule” from transplant centers in a number of states that implementation was suspended by Congress in 2000 [2]. The suspension proved to be transient with an amended “Final Rule” (Federal Register Volume 64, Issue 244) eventually passing in March 2000 [3], stipulating that organ allocation policies:

  1. Shall be based on sound medical judgment.
  2. Shall seek to achieve the best use of donated organs.
  3. Shall preserve the ability of a transplant program to decline an offer of an organ or not to use the organ for the potential recipient.
  4. Shall be specific for each organ type or combination of organ types to be transplanted into a transplant candidate.
  5. Shall be designed to avoid wasting organs, to avoid futile transplants, to promote patient access to transplantation and to promote the efficient management of organ placement.
  6. Shall be reviewed periodically and revised as appropriate.
  7. Shall include appropriate procedures to promote and review compliance.
  8. Shall not be based on the candidate's place of residence or place of listing.

As the “Final Rule” was making its bumpy way to passage, the Institute of Medicine was asked to review the impact of national organ allocation policies. In its report, the Institute of Medicine challenged the medical community to develop a points-based system that was derived from medical characteristics that reflected disease prognoses [4]. The challenge was ultimately met by the adoption of the MELD score [5, 6] in February 2002. The beauty of the MELD score is that it is generated from three almost entirely objective parameters (total bilirubin, creatinine and international ratio for prothrombin time) and has been widely validated as a means of predicting waitlist mortality. To accommodate patients with HCC, whose risk of death was not perceived as being reflected in the calculated MELD score, an exception MELD score of 24 points was assigned to patients with HCC. It was rapidly obvious that the number of MELD score exception points granted to patients with HCC was excessive. An analysis of the UNOS database in 2004 revealed that deceased donor transplant rate for patients with HCC more than tripled (p < 0.001) and the time to transplantation fell by 70% post-MELD (p < 0.001) [7]. Downward adjustments to the number of MELD exception points granted to patients with HCC in 2003 and again in 2005 has not had a meaningful impact on any of the metrics that demonstrate a disproportionate and unfairly high priority for patients with HCC [8]. Non-HCC patients with a MELD score of ≥28 have a 90-day mortality that is eight times higher than HCC patients (3% vs. 24%) [9]. The situation will inevitably be worsening since the analysis by Schuetz et al [1] through the enactment of UNOS's new “Share 35” policy, which was developed in response to the eighth principle of the “Final Rule,” that organ allocation shall not be based on the candidate's place of residence or place of listing. It might be argued that the second, fifth and sixth principles of the “Final Rule” should be given greater priority by policy-makers. The combined failures by UNOS to reduce the number of MELD exception points awarded to patients with HCC and, regional variances notwithstanding, the inclusion of patients with HCC in “Share 35” will inevitably result in further loss of life among patients whose MELD scores are calculated rather than assigned. In addition to allocating donor organs to patients who are not the most medically in need, the current policies contribute to (and possibly cause) the relentless increase in MELD scores required to undergo liver transplantation (“MELD creep”) and to perceptions that organ allocation is unfair. Erosion of equity in organ allocation may exacerbate the shortage of donor organs, as perceived fairness in organ allocation is an important determinant of organ donation rates [10]. The time to act is now. It has been for the last 7 years.

Disclosure

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  2. Disclosure
  3. References

The author of this manuscript has no conflicts of interest to disclose as described by the American Journal of Transplantation.

References

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  2. Disclosure
  3. References
  • 1
    Schuetz C, Dong N, Smoot E, et al. HCC patients suffer less from geographic differences in organ availability. Am J Transplant 2013; 13: 29892995.
  • 2
    Grantham D. Transforming transplantation: The effect of the health and human services final rule on the organ allocation system. San Francisco Law Rev 2001; 35: 751782.
  • 3
    Hussong S. Administrative developments: DHHS issues organ allocation final rule. J Law Med Ethics 1999; 27: 380382.
  • 4
    Institute of Medicine Committee on Organ Procurement and Transplantation Policy. Organ procurement and transplantation: Assessing current policies and the potential impact of the DHHS final rule, Vol. 1. Washington, DC: National Academy Press, 1999, pp. 138.
  • 5
    Malinchoc M, Kamath PS, Gordon FD, Peine CJ, Rank J, ter Borg PC. A model to predict poor survival in patients undergoing transjugular intrahepatic portosystemic shunts. [See comments.] Hepatology 2000; 31: 864871.
  • 6
    Wiesner RH, McDiarmid SV, Kamath PS, et al. MELD and PELD: Application of survival models to liver allocation. Liver Transpl 2001; 7: 567580.
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    Sharma P, Balan V, Hernandez JL, et al. Liver transplantation for hepatocellular carcinoma: The MELD impact. Liver Transpl 2004; 10: 3641.
  • 8
    Sharma P, Harper AM, Hernandez JL, et al. Reduced priority MELD score for hepatocellular carcinoma does not adversely impact candidate survival awaiting liver transplantation. Am J Transplant 2006; 6: 19571962.
  • 9
    Goldberg D, French B, Abt P, Feng S, Cameron AM. Increasing disparity in waitlist mortality rates with increased model for end-stage liver disease scores for candidates with hepatocellular carcinoma versus candidates without hepatocellular carcinoma. Liver Transpl 2012; 18: 434443.
  • 10
    Boulware LE, Troll MU, Wang NY, Powe NR. Perceived transparency and fairness of the organ allocation system and willingness to donate organs: A national study. Am J Transplant 2007; 7: 17781787.